Steering-gear



c. M. MANLY.

STEERING G EAR. APPLICATION FILED AUG.23| ISI?.

1,389,260. Patentemg. 30,1921..

2 SHEETS-SHEET I.

C. M. M-ANLY.

v STEERING GEAR.

APvLlcATloN FILED Aue.23, 1911.

Patented Aug. 30, 1921'.

y 4 2 SHEETS-SHEET 2 @MRT/wm l of this character.

CHARLES M. MANLY, OF BUFFALQ, NEW YORK.

lITED STATES PATENT OFFICE.

STEERING- GEAR.

specification of Letters Patent.

Patented Aug. 30, 1921.

Application led August 23, 1917. Serial No. 187,896.

To @ZZ whom it may concern.'

Be it known that I, CHARLES M. MANLY,

a citizen of the United States, and a resident of Buffalo, county of Erie, and State of New York, have invented new and useful Improvements in Steering-Gears, of which the following is a specification.

This invention relates to 'steering gear for ships, etc., and has for its object to provide a power driven gear which shall embody the advantages of the irreversible raulic or steam cylinder, with the advantages of quick response to the helm and simplicity of design, but without the disadvantage'heretofore inherent in a mechanism of this type of being reversible under the reactionof a greater pressure on the rudder than the operating pressure, whereby the steering of the boat is rendered unreliable and the parts subject to excessive strain.

A further object` of the invention is to provide a steering gear embodying the advantages of direct application of power and .irreversibil'ity as above described, in which the rudder is moved in synchronism, both as regards speed and* position, with the steering wheel, while using as a prime mover a continuously running motor of uniformspeed thereby facilitating the use of an electric motor without danger of overload or other injury. v

With the above objects in View, my invention consists primarily of a screw mechanism for moving the rudder and also reciprocating thrust cylinders connected to the' rudder for simultaneous operation with the `.screw mechanism, both the screw mechanism and the thrust cylinder being operated from \a common variable stroke pump, the pump being adapted to be driven from a suitable prime mover at a constant speed. The fluid connections between the pump and the thrust cylinders and the motor for operat ing the screw mechanism will be such that the thrust cylinders primari-ly effect the operation of the rudder, the motor driving the screw mechanism merely consuming sufiicient power to rotate the screw as the load is relieved .by the thrust cylinders. In the accompanying drawings, I have illustrated a preferred lpractical einbodinient of myinvention, and in said drawings,

. *igure 1 is a plan view showing my improved steering gear;

Fig. 2 is a side elevation ofthe mechanism shown in Fig. l; and

Figs. 3 and 4 are detail views which will be later described.

Referring to the drawings, l indicatesv the rudder post of the ship, whose deckline is indicated at 2 in Fig. 2. The rudder post is provided on its upper end with a ci'oss arm 3 to whose opposite ends are connected thelinks 4, by which the rudder is actuated. To the opposite ends of the links 4 are connected oppositely positioned nuts 5 -and 6 respectively, working on a screw 7 whose ends are oppositely threaded, as shown in ig. 1, so that when the screw is rotated vthe nuts 5 and 6 will be moved toward or away from each other, accoid-v ing to the direction of rotation of the screw.

n` such movement of the nuts, the rudder will be turned in one direction or the other, both links 4 being operative, =011e pushin and the other pulling, according to the d1- rection of rotation of the screw.

The mechanism so far described is a standard form of steering gear which is generally. accepted as the most reliable because of the irreversibility of its screw conf nections and the simple positive connection between the screw and the rudder. For actuating the screw 7 I'have provided in the preferred embodiment o f my invention which is described in the drawing, a hydraulic variable slpeed gear of the type shown in my prior atent No. 801,097, dated October 3, 1905, and in my copending application N o. 639,464. This mechanism consists brieiiy. of a variable stroke pump 8 continuously driven from an electric motor 9, or lother prime mover, and connected through a closed fluid circuit with a hydraulicV motor 10 whereby the shaft l11 of the motor will be driven at varying speeds, depending on the length of pump stroke.

The shaft 11 is connected to the screw 9 by means of a clutch 12 through which a large'gear 14 on' the end of the screw 7 is driven by means of an intermediate gear 13. -The stroke of the pump is controlled by means of a. rod 15 in such manner that the extent of adjustment of .the rod on opposite sides of itsA central neutral position determines the length of pump stroke. The rod A15 is actuated by link 16- connected in any suitable manner, not shown, to the steering wheel. The link 16 is connected to the Vrod 15 by` a floating lever 17 attached at its middle point to the link 16 and atits ends to the rod and the nut 5, respectively. By means 0f this construction, upon actuation of the link 16 by the steering wheel, the lever 17 will turn on its connection with the "nut 5 as a fulcrum and shift the rod 15 in tion with the iever'17 to move the lever in the stroke of the hydrauliqpump will notv the opposite direction to that effected by the steeringwheel, so that when `thespeed of movement of the hydraulic. motor corresponds with the speed of the steering wheel be furtheradjusted and the hydraulic motor ``will continue in motion at auniform speed.

Vhen the rudder'has been adjusted to the Ydesired position, the movement of the steering wheel will be stopped and the continuing movement of the nut 5 will cause the lever 17 to turn on its-connection withthe link16 as a fulcrum andrapidly turnthe rod 15 The mechanismso far described constii Ato its Zero position,` thereby` stoppingthe rudder and holding it in itsadjusted position by means of the irreversible screw 7.

"'tiites aV complete steering gear,"altliough "there is usually -associated with such gear, an auxiliary power'mechanism,-wlnch I `have ""indicated merely -by the shaft A20, for use in 'elise the hydraulic mechanism .is disabled, and also an auxiliary shaft21 which may be hand-operated in case both the devices are disabled.

' but is open to the objection that because of the low mechanical eiiciency of the screw gear it consumes a much larger amount of power than necessary for the actual shiftingr of the rudder. The principal object o f my present invention is to obtain all the advantages of this screw gearjbut at the same time obviate the friction loss in the transmission whereby the horse power of the prime mover may be reduced to less than one third of the horse power which has heretofore been Longitudinal move-A Thesel shafts are provided with suitable'clutches whereby they are nornecessary. To this end I place beneath the nuts 5 and 6 and parallel therewith, fixed hollow shafts 30, 30a, respectively, to each of which is attached at a point corresponding with the middle of the screw 7, a solid piston 31. The pistons 31 work in the cylinders 32, 32a which surroundthe shafts 30, 30, and are slidably mounted on said shafts and actuated by fluid pressure from the hydraulic pump, as will now be described.

The shafts 30, 30a, whose bores are divided at the center, are providedfon each side of the pistons 31 with transverse bores connecting the longitudinal passages of the shafts with the opposite .ends of the cylinders. 34 forming the connection between the pump andv inotor of the hydraulic gear, `are branch lpipes 33a, 34, respectively, the pipe '33rl being connected to the shaft 30 below the nut 5 at the end adjacent the gear ,14, and to the shaft 30 below the nut 6 at the end adjacent the rudder. The pipe 3,4@ is similarly connected to the shaft 30a below the nut 6 at the inner end, and tothe shaft below the nuta aty the outer end, whereby when fluid pressure is generated in the hydraulic gear, the cylinders 32, l32, will beshifted in the same directions respectively as the screw T tends to move the nutsii and 6.` The nuts and 6 are connected to their cylinders 32, 32l by forks 35 depending from each nut near each end thereof. The prongs Aof thc- Leading from each of the pipes forks embrace' the/cylinders and ther two"y forks of each are spaced apart to" fit between lugs 36 projecting from opposite sidesof the cylinders adjacent their ends. -f

By turning the.' cylinders around their shafts, which maybe accomplished with very little power, the 'cylinders may be locked to 1the nuts or may b e disconnected therefrom if it is desired to` operate the steering gear through means of the shafts 2O or 21.

f Then the rudder is ,to beactuatedby the t hydraulic gear the cylinders32, ,32? are connected to their respective nuts and the steering wheel operated just asA described above. i'

When the pump is. setin motion,

fluid under pressure will be delivered to i one or the other of thepipes 33, 34;, from which it willV tend to pass both. into the rotary motor 10 andthe 'corresponding ends Aof the cylinders 32, 32a. As the motor 10 and the cylinders 32, 32"1 are connected in paralleh it is obvious that the fluid will tend to pass into whichever offers the least resistance to movement.` Hence, by having the motor 10 quite small, and the cylinders i,

32v large, practically all the work of shifting the rudder will fall on the cylinder 3 2, the motor 1() merely serving to turn the screw 7 as the pressure on its threads is relieved by the action of the cylinders 32.

As stated above, the friction loss of .the screw 'gear is about 75% 'of the power applied, and as friction is directly proportional to the pressure of the engaging parts, it is obvious that by relieving this pressure through the directly-acting and practically frictionless hydraulic cylinder, lthe friction loss may be reduced to merely the rubbingv contact of the lightly rotating parts. The screw mechanism loses none of its advantages of irre'versibility, etc., in my construction, but on the contrary is relieved from wear so as to be practically indestructible.

`Moreover, the pressure in the cylinders tends constantly to relieve the screw thread of' pressure so that the 'force of the reaction against the rudder 1s reduced to a correspondiug'extent and all danger of breakage from sudden shock i practically eliminated.

The ordinary lit of the threads on the'nuts 5 and 6 on the screw shaft will allow suflicient lost motion between the thrust cylin` der and the rotary motor for the cylinders to relieve the pressure on the threads in advance of the rotary movement of the screw shaft, but if desired, a positive lost motion may be provided by counter-boring the nuts 5 and 6 at their bearing on the shaft and inserting threaded sleeves having a slight lost motion connection with the body of the nut itself.

The mechanism many obviously be otherwise modified, but I prefer the simple,

directly connected construction above de-` power-transmitting .screw simultaneously with the-application of power to said reversible power-actuated member. l

3. A po-wer-transmitting mechanism for transmitting power in opposite directions comprising a driven pc rt, a directly connected Huid pressure actuated member for shifting said part in opposite directions, a power operated auxiliary driving mechanism4 for said part comprising an irreversible driving member, and means for simultaneously operating said drving devices in such manner that the fluid pressure actu'- ated part acts in advance of the auxiliary.

threadedin said .ously rotatingsaid screw and supplying mechanism to substantially relieve the latter of the. driven load.

' 4. A power-transmitting mechanism for transmitting power in opposite direct-ions comprising a vdriven part, a directly connected Huid pressure actuated member for shifting said part in opposite directions. an auxiliary driving mechanism for said part 'comprising' an irreversible driving.

member, fluid pressure mechanism for operating said irreversible driving means, and

Vmeans for simultaneously applying fiuid pressure to both said mechanisms.

5. A power transmitting mechanism for transmittingl power in opposite directions comprising a driven part, a directly con- 'nected flmd pressure actuated member for shifting said part in opposite directions,.an auxiliary driving mechanism for said part comprising an irreversible driving member, a source of fluid pressure, and connections in parallel between said source of pressure and each of said mechanisms'whereby the mechanism offering the least resistance will be actuated in advance of the other mechanism.

6. In a power-transmitting mechan1sm,the

combination of a reciprocating partto be operated, a power cylinder, direct connections between the driving member of said cylinder and said part, an irreversible screw threaded in said part, and power operated means for simultaneously rotating said screw and supplying fluid pressure to said cylinder.

7. In a power-transmittingmechanism,the combination of a reciprocating part to be operated, a power cylinder, direct connections between the driving member of said cylinder and said part, an irreversible screw part, means for simultanefluid pressure to said cylinder, said means comprising a hydraulic motor, and a common source of fluid and power cylinder.

8. In a power transmitting'y mechanism, the combination of areciprocating part to be operated, a power cylinder, direct connections between the driving member of said cylinder and said part, an irreversible screw threaded in said part, means for simultaneously rotating said screw and supplying fluid pressure to said cylinder, said mea-ns comprising a hydraulic motor having operative connection with said screw, and a variable stroke pump having Huid transmitting connections with both said motor and said power cylinder.

9. In a power transmitting mechanism, the combination of a reciprocating part to be operated, a power cylinder, direct connections between the driving member of' said cylinder and said part, an irreversible screw threaded in said part, means for simultaneously rotating said screw and supplying Huid pressure for said motor whereby the pressure from said pump willV operate either the cylinder or motor in advance of the other, depending uponhtheir relative resistance.

10. In a steering gear the combination of a rudder yoke, oppositely movable nuts Afor shifting said yoke, screw mechanism for op- `eratin said nuts reci rocatinor drivin members connected to said nuts, and means for simultaneously rotating said screw and reciprocating said members.

11. In a steering gear the combination `of a rudder yoke,roppositely movable nuts for shifting said yoke, screw mechanism for operating said nuts, power cylinders connected to said nuts, and means for simultaneously rotating said screw and supplying operating pressure to said cylinders.

12. In a steering gear the combination of a rudder yoke, oppositely movable nuts for shifting said yoke, screw mechanism for op- @rating said nuts, power cylinders having reciprocating driven parts att-ached to said nuts, a hydraulic motor for operating'said screw mechanism, and means for simultaneously supplyingsaid power cylinders and hydraulic motor wit-h Huid pressure.

13. In a' steering gear the combination of airudder yoke, oppositely movable nuts for shifting said yoke, screw mechanism for operating said nuts, power cylinders having -reciprocating driven parts attached to said shifting said yoke, screw mechanism for operating said nuts, power cylinders having reciprocating driven parts attached to said nuts, a hydraulic motor for operating said screw mechanism, and means for simultaneously supplying said power cylinders and hydraulic motor with'iiuid pressure, said means comprising a variable stroke pump having operative connections between the stroke-varying means and the wheel or helm of the vessel, said connections comprising a differential mechanism connected to a driven part of said steering gear for shifting the stroke-varying member in opposition to the movement effected by the steersman to maintain the operation of the rudder in synchronism with the helm or wheel.

Signed at Buffalo, in the county of Erie` and State of New York, this 29 day of March, 1917. l

CHARLES M. MANLY. 

